Nonsugar sweeteners such as aspartame, stevioside, saccharin sodium, thaumatin, glycyrrhizin, acesulfam-K and sodium cylcamate, which are several hundreds of times as sweet as sucrose, are low-caloric and non-cariogenic. Thus the application ranges of these nonsugar sweeteners have been more and more extended as substitutes for sugar which is somewhat injurious to health.
However each of these nonsugar sweeteners has an extremely high sweetness which makes it almost impossible to employ the same alone for home use. Therefore the nonsugar sweetener is generally blended with fillers to thereby give a powder, or is sometimes further molded into an appropriate shape together with excipients. However these products thus obtained are similar to powdered or granulated drugs in appearance and thus are not accepted as conventional sweeteners.
On the other hand, sugar alcohols such as sorbitol, maltitol and xylitol having excellent sweetness characteristics are widely used as non-digestive, i.e., low-caloric and non-cariogenic sweeteners. There are known sweetening compositions comprising a mixture of these sugar alcohols with nonsugar sweeteners such as aspartame, stevioside or saccharin sodium. However, recent studies on rat, dog and human being suggest that these sugar alcohols would be decomposed and absorbed to a considerably high extent in vivo and thus the sugar alcohols are almost comparable to sucrose in caloric value. That is to say, these sugar alcohols are metabolized by enteric bacteria to thereby supply energy. In addition, these mixtures of sugar alcohols and nonsugar sweeteners have a drawback in appearance which shows similar to powdered or granulated drugs, as described above.
The inventors have previously proposed an invention on a taste modifier for a nonsugar sweetener (JP-A-63 258557, the term "JP-A" herein used means unexamined Japanese patent application). According to the prior invention, one part by weight of mesoerythritol is preferably blended with, for example, 0.001 to 0.007 part by weight of stevioside, 0.001 to 0.004 part by weight of glycyrrhizin, 0.001 to 0.014 part by weight of aspartame or 0.0004 to 0.001 part by weight of saccharin sodium. The inventors have further proposed a low-caloric sweetening composition wherein a surface of microcrystalline particles of mesoerythritol is coated with a sweetening component containing at least one nonsugar sweetener (see JP-A-I-95741 and JP-A-I-98457). In the case of the two prior inventions, a mesoerythritol is preferably blended with a nonsugar sweetener at the same ratio as those defined above.
Thus a sweetening composition similar to sucrose in sweetness characteristics can be obtained by blending mesoerythritol with a nonsugar sweetener at the ratio defined above. However, the inventor have subsequently found that the mesoerythritol contained in a large amount in a sweetening composition, which is obtained by blending mesoerythritol and a nonsugar sweetener so as to give a sweetness characteristics similar to those of sucrose, would require heat dissolution when added to hot coffee or hot tea, thereby resulting in a significant decreasing a temperature of the hot coffee or hot tea. Therefore the above sweetening composition is impossible to add to hot coffee or hot tea in the same manner as that employed in the case of sugar.